Marine lantern assembly



Nov. 30, 1965 s. A. HEENAN ETAL 3,

MARINE LANTERN ASSEMBLY Original Filed July 29, 1960 5 Sheets-Sheet 1 INVENTORS. SIDNEY A. HEENAN ROBERT I. NAGEL ATTOZNEY Nov. 30, 1965 s. A. HEENAN ETAL 3,221,162

MARINE LANTERN ASSEMBLY Original Filed July 29. 1960 5 Sheets-Sheet 2 NVENTORS SIDNEY A. HEENAN ROBERT I. NAGEL BY 0 Arrijiif Nov. 30, 1965 s. A. H-EENAN ETAL 3,221,162

MARINE LANTERN ASSEMBLY Original Filed July 29. 1960 1 5 Sheets-Sheet 3 INVENTORS SIDNEY A. HEENAN ROBERT I. NAGEL ATTM Nov. 30, 1965 s. A. HEENAN ETAL. 3,221,162

MARINE LANTERN ASSEMBLY Original Filed July 29. 1960 5 Sheets-Sheet 4 INVENTORS SIDNEY A. HEENAN ROBERT I. NAGEL BY 2 Nov. 30, 1965 s. A. HEENAN ETAL 3,221,162

MARINE LANTERN ASSEMBLY Original Filed July 29. 1960 5 Sheets-Sheet 5 LUKE;

EEK LB 360 INVENTORS SIDNEY A. HEENAN ROBERT I. NAGEL BY 3 z ATTOQtVZj United States Patent 3,221,162 MARINE LANTERN ASSEMBLY Sidney A. Heenan, Park Ridge, and Robert I. Nagel, Skokie, lll., assignors to Elastic Stop Nut Corporation of America, Union, N.J., a corporation of New Jersey Continuation of application Ser. No. 46,246, July 29, 1960. This application May 8, 1963, Ser. No. 278,903 7 Claims. (Cl. 240-22) This application is a continuation of our application entitled Marine Lantern Assembly, bearing Serial No. 46,246, filed July 29, 1960, and now abandoned.

The present invention relates generally to marine aids to navigation and pertains more specifically to an improved construction for minor light apparatus in the form of an improved integrated modular signal lantern assembly which projects an omnidirectional visual signal of uniform intensity and may readily and selectively provide a monodirectional 0r multi-directional signal beam of increased intensity at a desired azimuth.

Conventional minor light devices are generally employed on buoys, beacons, channel lights, aviation obstructions and like installations where the display of visual signals is an effective means for warning of hazards and aiding navigation. 'Such units are usually unattended, except for periodic maintenance. The apparatus essentially consists of a drum-type lens unit in a corrosion resistant housing with a light source properly located relative to the lens, and a flasher assembly for intermittently operating the light source. Since such units are usually self-contained, the light source is battery powered and an automatic lampchanger mechanism is included. The drum-type lenses employed in these conventional devices may be either omnidirectional or may have facilities for projecting a single, highly directional beam and are generally fabricated of glass, either cut and polished glass for high optical efficiency, at a consequent high initial cost, or pressed glass with an appreciably reduced optical efiiciency, at a somewhat lesser initial cost. Such glass lenses together with the housings required therefor constitute a relatively heavy and expensive unit.

In certain installations it is desirable to provide not only an omnidirectional visual signal, but a highly directional beamed signal of relatively high intensity in at least one, and often more than one, specific azimuth in addition to the omnidirectional signal. The cost of designing and fabricating lenses to satisfy the many and varied combinations of beamed signals required at various installations, as well as the requirements imposed bysignal needs between these directional beams has, even for pressed glass lenses, been economically unfeasible. Alternatives, such as the utilization of multiple monodirectional drum-type lens units or the use of combinations of omnidirectional and directional units, although of lesser initial cost, are equally uneconomical due to increased operating and maintenance costs.

An important object of the invention is to provide an integrated marine minor light in the form of a modular lantern assembly for projecting an omnidirectional visual signal, the lantern having facilities for selectively and readily providing a monodirectional or a multidirectional beamed signal of relatively high intensity at selected azimuths in addition to the omnidirectional signal.

Another object of the invention is to provide an improved construction for marine lanterns of greatly reduced size, weight and cost.

A further object of the invention is the provision of an improved construction for marine lanterns having improved performance characteristics and providing marked economies of operation and in required maintenance.

The invention may be described briefly as a signal 3,221,162 Patented Nov. 30, 1965 lantern for projecting a signal visible throughout a given area, the signal being substantially uniform except for at least one zone of increased intensity. The lantern has an omnidirectional lens with a series of colli-mating lens elements lying in parallel planes for accepting light emanating from a point source and concentrating the light in planes perpendicular to the parallel planes and passing through the source to project a signal of uniform intensity throughout the given area. An auxiliary lens panel is provided and is capable of being selectively located relative to the omnidirectional lens so as to intercept a sector of the projected signal, the panel having a series of collimating lens elements lying in at least some of the. perpendicular planes for accepting light from a portion of the omnidirectional lens and concentrating such light in the parallel planes into a zone of increased intensity thereby forming a directional beam within the visual signal. Means are provided for selectively locating the panel relative to the omnidirectional lens to orient the beam at a desired azimuth and for securing the panel in that location. The extent of the lens elements of the panel in the perpendicular planes may be less than the extent of the omnidirectional lens in that same direction so that at least a portion of the signal projected by the omnidirectional lens is visible around the complete periphery of the lens without being intercepted bythe panel. Additionally, another series of lens elements may be prvided in the panel adjacent the first series of lens elements and lying in the perpendicular planes for accepting light from a further portion of the omnidirectional lens and redistributing such light into a zone contiguous with the zone of increased intensity so as to preclude the format-ion of a shadow area in the contiguous zone.

The novel features of the invention both as to its structure and method of operation, as well as additional objects and advantages thereof, will be more fully under stood from the following detailed description of an embodiment of the invention when read in conjunction with the accompanying drawings in which:

FIGURE 1 is a perspective view, partially sectioned,

illustrating an assembled bidirectional signal lantern constructed in accordance with the invention;

FIGURE 2 is a partially diagrammatic sectioned elevati-onal view of a monodirectional signal lantern constructed in accordance with the invention;

FIGURE 3 is an elevational view of an auxiliary lens panel;

FIGURE 4 is a plan view of the panel of FIGURE 3;

FIGURE 5 is a sectional view taken along line 55 of FIGURE 3;

FIGURE 6 is an enlarged sectional view of a of FIGURE 2;

FIGURE 7 is a diagrammatic illustration of the operation of the auxiliary lens panel of FIGURE 3;

FIGURE 8 is a chart illustrating the operation of a signal lantern projecting an omnidirectional signal of uniform intensity;

FIGURE 9 is a chart similar to FIGURE 8 but showing a monodirectional beam of increased intensity in a signal by virtue of the utilization of an auxiliary lens panel; and

FIGURE 10 is a chart similar to FIGURE 9 showing a bidirectional signal obtained from the employment of two auxiliary lens panels.

1 Referring now to the drawings, and more particularly to FIGURES 1 and 2, an assembled signal lantern is shown in each figure constructed in accordance with the invention with portions of the assembly being sectioned to illustrate certain component parts. The lantern assembly has a base member 10, fabricated of a corrosion resistant material, upon which a lens assembly mounting ring 12 is supported and secured in place by a plurality portioni of captive wing screw members 14 (also see FIGURE 6). The base member 10 is provided with a mounting flange 16 for fixing the lantern assembly to a support member at the installation site.

A visual signal is provided in the lantern assembly by means of a light source, illustrated in the form of a lamp 20 having a filament 22 which is properly located relative to the optical components of the assembly as will be pointed out more specifically hereinafter. The lamp 20 is electrically connected to and intermittently operated by a flasher unit, the design and construction of which are well known to those skilled in the art and hence are not set forth in detail. It is sufficient to note that the flasher unit is preferably located within the base member 10 which provides adequate space and protection for such a unit.

In order to assure that an operating light source is available within the lantern assembly, at a proper location, at all times with a minimum of maintenance, the lamp 20 is mounted in a lampchanger mechanism which itself is fixed in place upon the base member 10. The lampchanger mechanism is an item of standard manufacture and is readily available commercially; hence, the details of design and construction need not be specifically set forth herein. Electrical access to the interior of the base member 10 and hence to the flasher unit and the lampchanger mechanism is preferably attained through at least one threaded aperture 24 which is adapted to receive, in gas and watertight relation, a suitable electrical cable connector.

In order to control and properly distribute the light emanating from the source and project a visual signal throughout a predetermined area, a generally cylindrical drum-type fresnel lens 30 is provided and encircles the light source 20 as best seen in FIGURES l, 2 and 7. As shown in the illustrated embodiment, the drum-type lens 30 is preferably in the form of an open-topped, frustroconical configuration and has a series of ring-like collimating dioptric elements 32 in the outer surface thereof, the lens elements 32 lying in parallel horizontal planes. The omnidirectional lens 30 is supported upon the lens assembly mounting ring 12 by means of integral extending feet 36 spaced around the periphery of the base of the lens 30 and is fixed in place relative to the light source 20 so that the focal point F of the lens coincides with the filament 22 of the light source 20, as illustrated in FIGURE 2. Thus, the drum-type lens 30 accepts light emanating from the filament 22 and lying in vertical planes, as shown by rays A diverging from point F toward the lens 30, and retracts such light to concentrate the light within such vertical planes, which planes pass through the filament 22, to project a visual signal of essentially uniform, or constant, intensity throughout the entire 360 periphery of the lens 30.

In the specifically illustrated lens, the drum is 250 mm. in diameter at the focal plane and is about 315 mm. high. The lens is an integral precision plastic molding with sharp, accurate prisms and is fabricated of clear methylmethacrylate resin, such as Plexiglas, manufactured by the Rohm and Haas Corporation, or Du Ponts Lucite molded under approximately 20,000 p.s.i. at a temperature of 450 F. Methylmethacrylate has a transmission factor of 92%, a refraction index of 1.493 and the illustrated lens has an acceptance angle of 110". Such a precision plastic lens has optical qualities approximately double that of pressed glass lenses and closely approximating those of cut and polished glass lenses and yet weighs only about one-tenth as much.

As best seen in FIGURES 1 and 2, the lantern assembly includes a generally cylindrical lens cover member 40 to protect the drum-type lens 30 and to furnish the desired color, i.e., either clear for a white signal or red or green as may be required in any given installation. The lens cover is preferably molded of the same material employed for the drum-type lens. As shown, the lens cover member 40 is shaped to complement the configuration of the lens 30 and as such is generally cylindrical in shape with a small taper narrowing toward the top and is dimensioned to be disposed in uniform spaced relation from the outer surface of the drum-type lens 30. The top 42 of the lens cover member 40 is domed, the dome having a rather large radius.

In order to support the lens cover member 40 upon the lens assembly support ring 12 and properly locate the optical components of the lantern assembly relative to one another, as well as relative to the base member 10 and consequently the light source 20, the base portion of the lens cover member 40 is provided with a narrow outwardly extending peripheral flange 44 which has an internally disposed undercut peripheral recess 46. As best seen in FIGURE 2, the recess 46 receives feet 36 of the drum-type lens 30 to properly locate lens 30 relative to the cover member 40. A series of inwardly extending V-shaped teeth, one of which is shown at 48 in FIGURES 6 and 7, are formed integral with the flange 44 and project into recess 46 for purposes which will be more fully explained below.

As explained hereinbefore, in certain installations it is desirable to provide not only an omnidirectional visual signal, but a highly directional beamed signal of relatively high intensity in at least one, and often more than one, specific azimuth in addition to the omnidirectional signal. Such directional beams are utilized, for example, in channel or range marking installations. In order to attain such a beamed signal, a condensing lens panel 50 is provided for each beam required and is best illustrated within the assembly in FIGURE 1. The condensing lens panels 50 are in the form of auxiliary fresnel lenses located between the drum-type lens 30 and the lens cover member 40 and, as best seen in FIGURES 1 through 7, each auxiliary lens panel has a series of vertically disposed collimating dioptric elements 52 symmetrically disposed on either side of a center line 54, and a further series of dioptric elements 55 adjacent the elements 52 along each longitudinal edge of the panel for purposes which will be explained hereinafter. In the illustrated embodiment, the auxiliary lens panels are generally in the form of a section of a cone and are of a configuration complementary to the drum-type lens 30 and the lens cover momber 40 so as to be capable of being placed between the lens cover member 40 and the lens 30. The panels 50 are preferably molded of the same material as the drum-type lens, i.e., methylmethacrylate.

As illustrated, the lens panel is preferably of a height somewhat less than the height of the drum-type lens 30 and is provided with an extending basal notched flange 56 haying the notches 58 thereof properly spaced so as to be engagable with at least one of the V-shaped teeth 48 disposed within the peripheral recess 46 of the lens cover member 40 for positioning purposes (see FIGURES 6 and 7).

The operation of each auxiliary lens panel 50 in providing a beamed signal of relatively high intensity is shown diagrammatically in FIGURE 7 and graphically illustrated in FIGURES 8 through 10. As explained hereinbefore, and illustrated in FIGURE 2, the drum-type lens 30 retracts light rays only in vertical planes and tends to collimate such light rays, while the distribution of light passing through the lens 30 is not affected in horizontal planes and hence such light continues along radial directions as seen in FIGURE 7, which is a diagrammatic plan view of a portion of the assembly of either FIGURE 1 or FIGURE 2. In the absence of an auxiliary panel, the visual signal projected by the lantern assembly would be essentially uniform, or constant, in intensity throughout the entire 360 periphery of the device, as illustrated in FIGURE 8. However, when an auxiliary lens panel 50 is located adjacent the drum-type lens 30 so as to intercept a sector of the signal projected by the lens 30 as shown in FIGURE 7, the collimating dioptric elements 52 of the auxiliary lens panel 50 lie in vertical planes and will refract light emanating from a portion of the lens 30 lying in horizontal planes to concentrate the light within such horizontal planes into a directional beam of relatively high intensity. Thus, light rays which radiate from filament 22 and are unaffected in horizontal planes by drum-type lens 30 are now intercepted by vertically disposed lens elements 52 and the light which would have filled the sector bounded by lines R is now concentrated into a zone of increased intensity bounded by rays B to form a directional beam of high intensity relative to the remainder of the omnidirectional signal as shown graphically in FIGURE 9. It is noted that the vertical distribution of light, as illustrated in FIG- URE 2, is unaffected by the presence of an auxiliary lens panel 50, but is affected only by the omnidirectional lens 30, the auxiliary lens panel 50 in FIGURE 2 afiecting only the horizontal distribution of light. Where more than one beamed signal is required, additional auxiliary lens panels 50 may be employed; thus, in FIGURE 1, two panels 50 are illustrated in the assembly to provide two beamed signals of increased intensity located 180 apart as graphically represented in FIGURE 10.

The auxiliary lens panels 50 are capable of being selectively positioned in the lantern assembly to locate each beamed signal relative to one another and to orient all of the beamed signals at a desired azimuth. As il lustrated in FIGURE 6, and diagrammatically shown in FIGURE 7, an auxiliary lens panel 50 is positioned in the lantern assembly with basal flange 56 projecting into the peripheral recess 46 of the lens cover member 40 and is located relative to the lens cover member 40 by virtue of one of the teeth 48 of the lens cover member 40 engaging a notch 58 in the basal flange 56 of the lens panel 50. A sufiicient number of teeth 48 and notches 58 may be provided so that any desired angle may be effected between multiple panels 50' and consequently between multiple beamed signals, each beamed signal being oriented by aligning the center line 54 with the desired azimuth.

The lens cover member 40 is oriented with respect to the lens assembly mounting ring 12 by virtue of pin 60 (see FIGURE 6) engaging a complementary groove 62 in the basal flange 44 of the cover member 40, the pin 60 being fixed within mounting ring 12. In order to secure the lens cover member 40 in place upon the lens assembly support ring 12, and consequently secure the drumtype lens 30 and the auxiliary lens panels 50 in place relative to the lens cover member 40 and upon the lens assembly support ring 12, a lens assembly mounting ring clamping member 64 is provided (see FIGURES 1, 2 and 6) which is held in place upon the ring by means of mounting bolts 66.

Returning now to FIGURE 7, because the light which would have filled the sector bounded by lines R is now concentrated into the zone of increased intensity bounded by rays B, a void, or shadow area, is created in the smaller sectors S lying between each ray B and each line R and a commensurate decrease in the intensity of the visual signal within these sectors S would occur as noted by the dotted curve T in the graphical representation of FIG- URE 9. However, some light will still remain in sectors S of the projected signal by virtue of the relative heights of the drum-type lens 30 and the auxiliary lens panel 50. Since the auxiliary lens panels are of a height somewhat less than the height of the drum-type lens, at least a portion of the 360 signal projected by the drum-type lens will not be intercepted by the auxiliary lens panel and will be visible uniformly around the entire periphery of the lantern assembly, thereby providing some light within the sectors S.

In order to distribute the light more evenly throughout that portion of the omnidirectional signal lying outside a directional beam and provide a more gradual transition from the essentially uniform omnidirectional signal to a directional beamed signal as represented graphically in FIGURES 9 and 10, the auxiliary lens panels are provided with the further series of dioptric elements 55 adjacent collimating elements 52 at each longitudinal edge of the panel. Dioptric elements 55 lie in vertical planes and have a concave, rather than convex, cross-section, as seen in FIGURE 7, so that light is accepted from further portions of the drum-type lens 30, which portions lie outside the sector defined by lines R, and through refraction is spread out in horizontal planes to redistribute the light from the sectors bounded by lines R and rays C and direct some of that light into sectors S as indicated by diverging rays D to preclude the formation of a shadow area in zones contiguous with the zone of increased intensity. Such a redistribution of light adjacent a directional beamed signal effects a more gradual transition from the constant intensity omnidirectional signal to the beamed signal by substituting a small decrease in signal intensity over a greater sector of the visual signal adjacent the beamed signal for a larger decrease in intensity over a smaller sector as illustrated in the dilference between the dotted curve T and the solid graphical representation in FIGURE 9.

It is essential for maximum performance that the filament 22 of light source 20 coincide with the focal point F, and the marine lantern assembly includes a simple but effective mechanism for accomplishing such a result, which mechanism is described and claimed in detail in the copending application of Arthur M. Troccoli, Serial No. 46,121, filed July 29, 1960, now US. Patent No. 3,061,259.

As will be apparent to those skilled in the art, the above described lantern assembly provides an optical performance comparable to that of cut and polished glass lenses, and double that of conventional lanterns employing pressed glass lenses, but effects such results with marked decreases in weight, size and initial cost. Additionally, the unit provides significant economies in the operation of unattended lights because of its production of equivalent or better effective candlepowers with reduced power requirements, particularly for multidirectional beamed signal installations, resulting in savings in battery costs and decreased service and maintenance costs. Of primary importance is the provision, for the first time, of an integrated system formed of a modular omnidirectional lantern of improved character that is readily and selectively convertible to a monodirectional or multidirectional signal lantern with selectably adjustable beamed signal azimuth in accordance with the particular dictates of the installation site.

It is to be understood that the above detailed description of a preferred embodiment of the invention is provided by Way of example only and is not intended to restrict the invention. Various details of design and construction may be modified without departing from the true spirit and scope of the invention as defined in the appended claims.

We claim:

1. A signal lantern for projecting a signal visible throughout a given area, the signal being uniform except for at least one zone of increased intensity, said lantern comprising:

(A) an omnidirectional lens having a series of collimating lens elements lying in parallel planes for accepting light emanating from a point source and concentrating said light within planes perpendicular to said parallel planes and passing through said source to project a signal of uniform intensity throughout the given area;

(B) an auxiliary lens panel capable of being selec tively located relative to said omnidirectional lens so as to intercept a sector of said projected signal, said panel having a series of collimating lens elements lying in at least some of said perpendicular planes for accepting light from a portion of said omnidirectional lens and concentrating said light 7 within said parallel planes into a zone of increased intensity thereby forming a directional beam within said visual signal; and

(C) means for selectively locating said panel relative to said omnidirectional lens to orient said beam at a desired azimuth and for securing said panel in said location.

2. A signal lantern for projecting a visual signal around the complete horizon, the signal being uniform except for at least one zone of increased intensity, said lantern comprising:

(A) a light source;

(B) a drum-type lens surrounding said source and having a series of horizontally disposed ring-like collimating lens elements for accepting light emanating from said source and concentrating said light within vertical planes passing through said source to project a signal of uniform intensity around the complete periphery of said lens;

(C) an auxiliary lens panel capable of being selectively located relative to said drum-type lens so as to intercept a sector of said projected signal, said panel having a series of substantially vertically disposed collimating lens elements for accepting light from a portion of said drum-type lens and concentrating said light within horizontal planes into a zone of increased intensity thereby forming a directional beam within said visual signal; and

(D) means for selectively locating said panel relative to said drum-type lens to orient said beam at a desired azimuth and for securing said panel in said location.

3. A signal lantern of claim 2 wherein said portion of said drum-type lens from which light is accepted by said auxiliary lens panel extends vertically a distance less than the vertical height of said drum-type lens.

4. A signal lantern of claim 2 wherein said auxiliary lens panel has a further series of substantially vertically disposed lens elements adjacent said series of collimating lens elements for accepting light from a further portion of said drum-type lens and redistributing said light into a zone contiguous with said zone of increased intensity so as to preclude the formation of a shadow area in said contiguous zone.

5. A signal lantern for projecting a visual signal around the complete horizon, the signal being uniform except for at least one zone of increased intensity, said lantern comprising:

(A) a base member;

(B) a light source mounted upon said base member and lying in a horizontal plane;

(C) an omnidirectional lens positioned on said base member and surrounding said source and having a series of ring-like collimating dioptric elements lying in planes parallel to and on either side of said horizontal plane for accepting light emaanting from said source and concentrating said light within vertical planes passing through said source to project a signal of uniform intensity around the complete periphery of said lens;

(D) at least one auxiliary lens panel capable of being selectively located on said base member adjacent said omnidirectional lens so as to intercept a sector of said projected signal, said panel having a first series of substantially vertically disposed collimating dioptric elements for accepting light from a portion of said omnidirectional lens and concentrating said light within horizontal planes into a zone of increased intensity thereby forming a directional beam within said visual signal; and

(E) means for selectively locating each said panel upon said base member relative to said omnidirectional lens to orient said beam at a desired azimuth and for securing each said panel in said location.

6. A signal lantern of claim 5 wherein each said auxiliary lens panel extends vertically a distance less than the vertical height of said omnidirectional lens so that at least a portion of said signal projected by said omnidirectional lens is visible around the complete periphery of said lens and is not intercepted by said panel.

7. A signal lantern of claim 5 wherein each said auxiliary lens panel has a second series of substantially vertically disposed dioptric elements adjacent said first series of elements for intercepting a further sector of said projected signal and redistributing the light from a further portion of said omnidirectional lens into a zone contiguous with said zone of increased intensity so as to preclude the formation of a shadow area in said contiguous zone.

References Cited by the Examiner UNITED STATES PATENTS 629,890 8/1899 Creveling 240-9 2,170,912 8/1939 Rolph 240-106 2,290,100 7/1942 Goris 340383 NORTON ANSHER, Primary Examiner. 

1. A SIGNAL LATERN FOR PROJECTING A SIGNAL VISIBLE THROUGHOUT A GIVEN AREA, THE SIGNAL BEING UNIFORM EXCEPT FOR AT LEAST ONE ZONE OF INCREASED INTENSITY, SAID LANTERN COMPRISING: (A) AN OMNIDIRECTIONAL LENS HAVING A SERIES OF COLLIMATING LENS ELEMENTS LYING IN PARALLEL PLANES FOR ACCEPTING LIGHT EMANATING FROM A POINT SOURCE AND CONCENTRATING SAID LIGHT WITHIN PLANES PERPENDICULAR TO SAID PARALLEL PLANES AND PASSING THROUGH SAID SOURCE TO PROJECT A SIGNAL OF UNIFORM INTENSITY THROUGHOUT THE GIVEN AREA; (B) AN AUXILIARY LENS PANEL CAPABLE OF BEING SELECTIVELY LOCATED RELATIVE TO SAID OMNIDIRECTIONAL LENS SO AS TO INTERCEPT A SECTOR OF SAID PROJECTED SIGNAL, SAID PANEL HAVING A SERIES OF COLLIMATING LENS ELEMENTS LYING IN AT LEAST SOME OF SAID PERPENDICULAR PLANES FOR ACCEPTING LIGHT FROM A PORTION OF SAID OMNIDIRECTIONAL LENS AND CONCENTRATING SAID LIGHT WITHIN SAID PARALLEL PLANES INTO A ZONE OF INCREASED INTENSITY THEREBY FORMING A DIRECTIONAL BEAM WITHIN SAID VISUAL SIGNAL; AND 